LeetCode Reverse Linked List II

Reverse a linked list from position m to n. Do it in-place and in one-pass.

For example:
Given 1->2->3->4->5->NULL, m = 2 and n = 4,

return 1->4->3->2->5->NULL.

Note:
Given m, n satisfy the following condition:
1 ≤ m ≤ n ≤ length of list.

题意：翻转某一段的链表。

思路：把这一段截取出来回文的形式交换。

/** * Definition for singly-linked list. * public class ListNode { *     int val; *     ListNode next; *     ListNode(int x) { *         val = x; *         next = null; *     } * } */public class Solution {    public ListNode reverseBetween(ListNode head, int m, int n) {         List<ListNode> list  = new ArrayList<ListNode >();  ListNode cur = head; for (int i = 1; i < m; i++) cur = cur.next;  for (int i = m; i <= n; i++) { list.add(cur); cur = cur.next; } int size = list.size(); for (int i = 0; i < size/2; i++) {int tmp = list.get(i).val;list.get(i).val = list.get(size-1-i).val;list.get(size-1-i).val = tmp; }  return head;    }}